Biomedical subjects
Publications and source records attributed to F Disant.
After a description of the physiopathology of facial ageing, the author specifies the interest of the biplane cervico-facial face lift to correct the tegumentary ptose of the lower third of the face. The various technical stages are described while insisting on the complementarity of the handing-over in tension of the SMAS (Superficial Musculo Aponevrotic System) and the redrap of the SACS (Superficial Adipo-Cutaneous System).
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BACKGROUND: Chronic exposure to ultraviolet (UV) radiation induces changes in the skin structure which are mostly found in the superficial dermis and at the dermal-epidermal junction. Keratinocytes and fibroblasts contribute both to the synthesis and to the degradation of the molecules important for the integrity of this skin site. While several studies have reported on alterations of dermal components and of the functions of fibroblasts in vivo and in vitro after UV exposure, recent data suggested that keratinocytes could be the main skin cell type involved in the photoageing process. OBJECTIVES: In this study, we analysed the expression of two keratinocyte molecules namely, beta1 integrin (a proliferation marker) and involucrin (a differentiation marker) in sun-exposed and sun-protected facial skin of 16 healthy patients undergoing facial lifting. METHODS: Methods included histology, immunohistochemistry and quantitative reverse transcriptase-polymerase chain reaction analysis. RESULTS: Sun-exposed skin displayed the characteristic morphological and molecular features of dermal photoageing, compared with sun-protected skin, including dermal elastosis, diminished fibrillin and type VII collagen expression. Analysis of the epidermis in sun-exposed vs. sun-protected skin showed no histological differences, but dramatic changes in the expression of beta1 integrin and involucrin. In sun-exposed skin, expression of beta1 integrin protein by epidermal basal cells was reduced, paralleling a downregulation of beta1 integrin mRNA, whereas involucrin protein expression was greatly enhanced in the superficial epidermal cell layers. Interestingly, the ratio between involucrin and beta1 integrin protein expression was consistently increased in sun-exposed skin sites. CONCLUSIONS: Collectively these results demonstrate that epidermal homeostasis is impaired by chronic UV exposure, and define beta1 integrin expression as a molecular marker of the epidermal photoageing process.
Facial hemi-atrophy affects 1 in 4000 or 5000 children. We propose treating this deformation of the 1st branchial arch with the "bone distraction" lengthening technique first described by Ilizarov in the 1950s, which has already been employed with the mandible. We have modelled mandibular distraction in facial hemi-atrophy patients and discuss the benefits of such pre-surgical planning encompassing the assistance of pre- and post-operative as well as surgically coordinated orthodontic therapy. Using X scanner views of a 5 year-old girl patient, we have developed a distraction-simulation software, which makes the pathological side harmonious with the healthy side along the medial sagittal plane. In order to obtain facial symmetry, put bones in balance, and orient the occlusal plane horizontally, essential requisites of occlusal stability, it is necessary: to employ a 2 or 3-dimensional distractor, to pre-plan the distraction and screw positioning, to set up a fixed orthodontic treatment plan prior to beginning distraction therapy.
Genetically-transferred hearing impairments account for more than 50% of cases of pediatric sensorineural hearing defects. Multiple clinical aspects are involved in genetic hearing impairment, including the involvement of other organs, genetic inheritance, and the degree and age at onset of hearing loss. Diagnosis relies on family history, on the systematic investigation of the symptomatology including an associated syndrome, and audiometry testing in parents and siblings. Analysis of the connexin 26 gene is also indicated, as it is frequently involved in this disorder. Further genetic analysis in affected families will aid in detecting other as yet unidentified genes responsible for hearing impairment.
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OBJECTIVE: To present our initial experience with sialendoscopy of the parotid duct. STUDY DESIGN METHODS: Diagnostic and interventional sialendoscopy procedures were performed in 79 and 55 cases, respectively. Diagnostic sialendoscopy was used to classify ductal lesions into sialolithiasis, stenosis, sialodochitis, and polyps. Interventional sialendoscopy was used to treat these disorders. The type of endoscope used, the type of sialolithiasis fragmentation and/or extraction device used, the total number of procedures, the type of anesthesia, and the number and size of the sialoliths removed were the dependent variables. The outcome variable was the endoscopic clearing of the ductal tree and resolution of symptoms. RESULTS: Diagnostic sialendoscopy was possible in all cases, with an average duration of 26+/-14 minutes and no complications. Interventional sialendoscopy was successful in 85% of cases, with an average duration of 73+/-43 minutes (+/- standard deviation). Multiple procedures were performed in 45% of cases, general anesthesia was used in 24%, and parotidectomy in 2%. Multiple sialoliths were found in 58% of ducts and associated with more procedures under general anesthesia and longer operations. The average size of sialoliths was 3.2+/-1.3 mm; larger stones were associated with more procedures under general anesthesia, longer and multiple procedures, use of fragmentation, and sialendoscopy failures. Sialolithiasis fragmentation was required in 10% of cases, with a success rate of 70%. Semirigid sialendoscopes performed better than flexible ones. Complications were mostly minor but were encountered in 12% of cases. CONCLUSIONS: Diagnostic sialendoscopy is a new technique for evaluating salivary duct disease, a technique which is associated with low morbidity. Interventional sialendoscopy allows the extraction of sialoliths in most patients, preventing open gland excision.
The authors report two new cases of inflammatory pseudotumours, sited in the pharynx and neck--sites in which no previous cases have so far been reported in the literature. The aetiology and clinical course of these rare benign tumours remain little understood even today. Their treatment is also not clearly described. This is most often surgical, although medical treatment is often very effective, and is sometimes appropriate. The authors begin by describing these two clinical cases, and then use the literature to give an account of the clinical course and treatment of inflammatory pseudotumours.
Diagnosis of hearing impairment is possible during the first days of life. Hearing tests are noninvasive and should not be delayed when hearing loss is suspected. Among children's hearing impairments, conductive hearing loss is the most frequent; it is generally acquired and reversible. At the opposite pole, sensorineural hearing loss has more severe consequences because it is irreversible and often present from birth. Early diagnosis and treatment are necessary in all cases to prevent speech delay. In cases with sensorineural hearing impairment, hearing aid fitting, or even cochlear implantation, and intensive speech therapy will help deaf children learn speech, with the view of optimal social and professional integration.
There are two procedures available for treatment of the agenetic pinna: reconstructive plastic surgery using costal cartilage, and bone-anchored prostheses. Both techniques are described, and the indications clarified. It is important to emphasise that all of the possible alternatives must be within the repertoire of the surgeon, so that the treatment can be adapted to suit the individual case.
Epithesis with bone anchoring can be usefully envisaged for the rehabilitation of losses of facial substance when reconstructive surgery is impossible, either for local or general reasons. It is important to ensure that patients are offered both methods, the advantages and disadvantages of which are analysed in this paper.
The authors describe a myocutaneous cervical island flap based on the submental vessels. The anatomy based on 12 fresh cadaver dissection is outlined the submental arteries were injected with methylene blue, and the flap design and technique were studied. The flap has a long, reliable pedicle and cutaneous dimension measured 10 x 5 cm. The flap has an excellent skin color match and wide are of rotation and can extend to the whole homolateral face, the whole oral cavity, the whole homolateral oropharyngeal. The donor site scare dissimulated under the mandible is perfectly acceptable.
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Acute perforations in the tympanic membranes (TM) of animals are not good models for assessment of materials used as graft membranes or of substances with the potential to activate tympanic membrane healing mechanisms for closing perforations. Most acute TM perforations heal spontaneously, in both animals and humans. Acute TM perforation models are not analogous to the pathologic human problem of long-standing TM perforation. Bilateral subtotal symmetric perforations, with each animal serving as its own control provide a suitable model. Fourteen dogs were operated. Subtotal perforation of TM in right ears were soaked with 2% glutaraldehyde to develop an animal model for persistent tympanic membrane perforation. Subtotal myringectomy was performed on left ears, without chemical treatment of the rim. Perforations were standardized in size. The healing pattern was evaluated weekly for a 15-week period. Six of the right ears and 14 of the left ears completely healed within 15 weeks. Statistically, the mean delay of closure was higher in the treated group than in the non-treated group, and the two groups were different according the closure rate criterion. Histologic analyses of persistent TM perforations and of healed cases were performed.
OBJECTIVE: To evaluate tolerance for this middle-ear implant and its effectiveness in eardrum healing under various pathologic conditions. SETTING: A 12- to 18-month follow-up case series at an institutional referral center offering hospitalized care. PATIENTS: Twenty-six eligible volunteers suffering from tympanic perforation or tympanic pocket retraction class II and III in Tos' classification. INTERVENTION: Patients underwent implantation with the type IV collagen film (film called "MTY" from the French membrane tympanique). The surgical procedure was similar to those using the temporal aponeurosis or the tragal perichondrium. OUTCOME MEASURE: Anatomic criteria was determined by otoscopy, and functional audiometric criteria was determined by air-borne gap measurements and by effects on cochlear function. RESULTS: Twenty-two of 26 patients were completely healed after 6 months, with no subsequent evolution. Nineteen of 26 subjects underwent a 1-year postoperative audiometric follow-up examination: 13 (68%) had an air-borne gap less than 10 dB, four (21%) had between 11 and 20 dB, and two (11%) had between 21 and 30 dB. Adverse effects included one patient whose MTY fell into the middle ear, three patients with transient myringitis, and one patient with otitis media with effusion. CONCLUSIONS: A human type IV collagen film may be a possible alternative to autologous tissue in tympanic membrane reconstruction. This new biomaterial was tested on patients with various diseases common in clinical otology, and demonstrated a good biocompatibility of MTY in the different pathologic conditions of chronic otitis media. A future randomized, controlled trial will randomly allocate patients to receive either MTY collagen film or tissue from the temporal aponeurosis.
Modifications of the total ear reconstruction technique allowing a two-stage procedure is described. However this is only possible if the soft tissue has not yet been damaged by previous plastic surgery or tympanoplasties. The framework sculpture is improved in order to obtain a posterior conchal wall at the first stage without using a skin graft. A tissue expander is used during the operative time in order to improve the framework coverage. A bone anchored hearing aid is preferred to tympanoplasty when necessary, for bilateral microtia. This method is effective and does not compromise the skin qualities. The osteointergrated implant is put in place during the second external ear reconstruction stage. The total hospitalisation period is no longer than 8 days.
Seven recent malignant external otitis are described. The authors report criteria of both etiology, bacteriologic, radionuclide scanning computed tomography. Now, for the positive diagnosis, the radionuclide scanning is essential. The computed tomographic scan provided the best anatomic imaging of the infection process. The treatment of choice is systemic antibiotic therapy as fluoroquinolones antibiotic. This antibiotic is active against P. Aeruginosa and has an excellent bone penetration. Only one patient died and another suffered from osteomyelitis of the base of the skull. The radionuclide scanning is very important for criteria of healing, particularly about stoppage of systemic antibiotic therapy.
The authors after a short morphological description of the microtia, expose the surgical evolution which had led to the actual auricular reconstruction technique, using a costal cartilage framework. This technique requiring several steps is exposed in the typical case of microtia. It is the preferential method. The difficult reconstructions due to the poor quality of the skin are exposed by degree of complexity: in these cases, tissue expansion, fascia temporalis superficialis can be useful and finally auricular prostheses, attached to bone-integrated implants, can be recommended. The functional surgery of the middle ear is also replaced in the context of the auricular reconstruction which is done around 8 years old.